Car bombs in Iraq kill 12, wound 30

Civilians inspect the aftermath of a car bomb attack while Baghdad municipality workers clean up in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Khalid Mohammed)
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Civilians inspect the aftermath of a car bomb attack while Baghdad municipality workers clean up in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Khalid Mohammed)
/ AP

Civilians inspect the aftermath of a car bomb attack while Baghdad municipality workers clean up in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Khalid Mohammed)— AP

Civilians inspect the aftermath of a car bomb attack while Baghdad municipality workers clean up in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Khalid Mohammed)
/ AP

Civilians inspect the aftermath of a car bomb attack while Baghdad municipality workers clean up in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Khalid Mohammed)— AP

Civilians inspect the aftermath of a car bomb attack while Baghdad municipality workers clean up in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Khalid Mohammed)
/ AP

Civilians inspect the aftermath of a car bomb attack while Baghdad municipality workers clean up in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Khalid Mohammed)— AP

Civilians inspect the aftermath of a car bomb attack while Baghdad municipality workers clean up in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Khalid Mohammed)
/ AP

People clean up at the scene of a car bomb attack in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Karim Kadim)— AP

People clean up at the scene of a car bomb attack in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Karim Kadim)
/ AP

An Iraqi man inspects the aftermath of a car bomb attack in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/Karim Kadim)— AP

An Iraqi man inspects the aftermath of a car bomb attack in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/Karim Kadim)
/ AP

People inspect the aftermath of a car bomb attack in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/Karim Kadim)— AP

People inspect the aftermath of a car bomb attack in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/Karim Kadim)
/ AP

A man lies in a hospital bed after being injured in a car bomb blast in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Karim Kadim)— AP

A man lies in a hospital bed after being injured in a car bomb blast in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Karim Kadim)
/ AP

A man lies in a hospital bed after being injured in a car bomb blast in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Karim Kadim)— AP

A man lies in a hospital bed after being injured in a car bomb blast in the Sadr City neighborhood in Baghdad, Iraq, Thursday, May 16, 2013. A car bomb exploded near a bus station in Baghdad's main Shiite district Wednesday, the deadliest in a series of explosions that killed and wounded dozens of people, nationwide, officials said. (AP Photo/ Karim Kadim)
/ AP

Baghdad police said the first blast struck a bus and taxi stop around rush hour in the eastern Sadr City neighborhood. Nine people were killed, including a 7-year old child, and 16 were wounded, two officers said.

Another car bomb hit a small market at a taxi stop in the eastern suburb of Kamaliya, killing three civilians and wounding 14 others, they said.

Two medical officials in a nearby hospital confirmed the causality figures. All officials spoke on condition of anonymity because they are not authorized to brief reporters.

The attack followed a wave of bombings on Wednesday that struck in mainly in Shiite neighborhoods, killing 33 people. At least seven of them died in Sadr City when a bomb in a parked car detonated at a bus stop.

The spike in violence comes amid growing tensions between the Shiite-led government and Iraq's Sunni minority over what they consider second-class treatment. A bloody government crackdown on militants last month in a protest camp in the country's north fueled the tension.

"We have to know that today's bloodshed is the result of sectarian hatred and also the result of a stirring up of these sectarian tensions," al-Maliki said at a government-sanctioned conference addressing atrocities committed under dictator Saddam Hussein. Incitement could be coming from inside or outside the country, he added.

No one immediately claimed responsibility for the Wednesday and Thursday attacks, but car and suicide bombings are a hallmark of al-Qaida's Iraq branch.

The spike in attacks, after a general decrease in violence, has raised fears of a return to the sectarian bloodshed that pushed the country to the brink of civil war in 2006-2007. Shiite militias have so far been largely restrained in their reactions to such bombings.